Snap-action governor



March 20, 1956 G. FLElscHEl. 2,738,968

SNAP-ACTION GOVERNOR Filed May 20, 1950 3 Sheets-Sheet l T 1:1.1A-

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EN? T13-4- INI/EN TOR. 671,5' 7M /2 5/5 c//EL 50 BY V fauw March 20,1956 G. FLElscHEl. 2,738,958

SNAP-ACTION GOVERNOR Filed May 20, 1950 I5 Sheets-Sheet 2 INVENTOR. QQS70/v /f/scf/Ez,

March 20, 1956 G. FLEISCHEL SNAP-ACTION GOVERNOR Filed May 20, 1950 3Sheets-Sheet 3 BY cmm United States Patent() p 2,738,968V p4staar-ACTION GovERNoR Gaston Fleischel, Paris, France; dedicated (bymesnieassignments) to the free use anti'benetit of the public A`Application May 20, 195o, sedative-163,240 4 Claims. (c1. 264-17)trifugal force, as the gradual speed increase operates againsttincreasedtensioning of theresisting spring or jump'between two -extrem'epositions as the speed exceeds or =drops below- Vpredetermined values,'-the former device` being clas'sitied as a static governorand'the latterVVas astatic governor. This'rnotion is Vfinallyl transmitted to amechanismwhich adjusts or modifies the operating com ance with thegovernor position.A Y v A i In a large iieldo applications, springloaded -govefors ditions ofthe apparatus sought tobe controlled inaccordcauses shifting of a control member lengthwise of the rotatingshift, or in any other directions through lever or other J operatingconnections.

Further and more specic objects of the present invention will in part beobvious and in part will be specifically .pointed out in the followingdescription of several illustrative embodiments of the invention.

in the drawings annexed hereto, and hereof,

Figure l is a vertical section through one form of device constructedaccording to and embodying the present invention, illustrating a singlegovernor with two spaced equilibriums and characterized by the absenceof linkage;

Figure 1A is a graphic illustration of the theoretical operation of thedevices in accordance with the present invention;

Figure 2 is a vertical section through another embodiment of myinvention as applied to a double governor with three equilibriumpositions and characterized by the absence o`f linkage;

Figure 3 is a vertical section through still another cmbodiment of thepresent invention as applied to `a double governor with threeequilibrium positions and characterized bythe absence of linkage;

Figure 4 is alvertical section through'a further embodiforming a .part

i ment lof ythe present invention as applied to a single have to 'beeifective only within aV :fairly narrow frange aroundone or severaldefinite speeds. It istlie aim-'of the 'inventionv to v`providea'fgvernor havi'n'g'a control member which determines-the working(conditions-Which shifts suddenly fromv yone operative position'to*another operative position. rlhissuddenppositive'shift'is thesnapaction referred-to "herein, In this invention, this" snap'- actionis achievedby giving to -the effective driving `force of the governorcontrol member, as Vthe motion begins, an excess of force over theopposing force of the spring, taking into consideration the variation ofthe strength ofsaid spring 'between two or more operative positions.

The main object of the present invention is the provision of a simplespring-loaded governor of the astatic type wherein the rate of increasein centrifugal force by movement of the rotating masses away from theaxis of `rotation a ainst kthe anta onistic s rin is in excess of theincrease in spring tension, above that of the preloading of said spring,in such a manner that any motion startedby the centrifugal forceovercoming the strength of the preloaded spring, is accelerated allalong the motion, whereby the snap-action effect is achieved.

Another main object of the present invention is the provision of aspring loaded governor providing a plurality of snap-actions resultingin shifting of a control member in stepped fashiorlk positively andsuddenly `from starting position to one or more successive spaced posi-"tions of equilibrium.

Other and associated main objects of the present invention are 'theprovision of a spring loaded governor lproviding a snap-action etectwherein the increased spring torce is suddenly overcome wholly by theincrease `in centrifugal force developed by the rotating masses; oralternately wherein the increased spring force is suddenly overcomepartly by the increase in centrifugal vforces developed by the rotatingmasses and partly by levers or linkage systems disposed within thegovernor or interposed between the governor and the opposed spring.

vAnother object of the invention is the provision of a spring-opposedsnap-action governor wherein thcmovemeut of masses outwardly from theaxis of rotation governor `with three equilibrium positions'andcharacterized by the absence of linkage;

' Figure :5 is a vertical section through a still further embodimentofthe present invention as applied to 'a governor providing snap actionresulting partly by mass movement and partly by internally arrangedvariable linkage;

Figures 6 and? are views partly in section and partly in side elevationof modifications of the present invention as applied to' governorsproviding snap action partly by mass movement and partly by externallyarranged levers;

Figure 8 is a similar View of a governor providing three equilibriumpositions partly by mass movement and partly by externally arrangedlevers;

Figure 9 is a similar view of a governor providing two equilibriumpositions partly by mass movement and partly by externally arrangedlevers, but operating at a variable angular velocity, in a predeterminedrange, in accordance with the requirements of the device connectedtherewith; and

Figures 10, l1 and l2 are similar views of the same type ofgovernorproviding a three position snap action, partly by mass movement andpartly by externally arranged levers, operating at two different angularvelocities, each variable in a given range, according to requirements ofthe device associated therewith.

In connection with the present invention, it will be demonstrated how agovernor can actuate a signal such as an electric signal having twooperative equilibrium positions, as signal on, signal oli.

Referring to Figure l, wherein means wholly within the governor areprovided to achieve the desired snapaction, a jump between twoequilibrium positions, my device is indicated generally by referencenumeral 10 n including a rotatable shaft 12 on which is axially fixedportion 3l) extending from a circle having a radius equal to thedistance between the center-line of shaft 12 and point 31. The normalspacing between shell 14v and plate24, at 23,' is that of 'the diameterof trapped vballs 22, Z2. The head 32 of sleeve 26 bears against-an arm34 fixed to a sliding shaft 36, behind which is-disposed [a helicalcompression spring 3S, positioned between sh'aft 36 and a suitable stop4t). The normal compression for the preloading of spring 38 urges shaft36, arn134`and sleeve 26 into the position of Figure 1 with the balls 22pressed against shell 10.

The axial shifting of collar 26 yand attached plate 24 is caused by theforce lof rotating balls or Weights 22 pushing against the inclinedsurface of the cone which engages the balls 22 when the resolved axialcomponent of said force against said surface is stronger than the forceof the biased or preloaded spring 38. This'occurs at a given angularvelocity, called hereafter the Vgovernor specific velocity; belowV saidvelocity due to spring 38 action, all parts remain inthe position shownin Figure l. When the action of balls on the engaged surface ofthe cone30 overcomes the force'of spring 3S, the cone 3i) and hub 26 begin asliding motion toV the'left, as in Figure l, 'thereby compressing thespring 33 and increasing the force of the spring 38 urging the cone 31Band the hub 26 to the right. Y Y 7 To overcome this increase ofresistance of spring 3S against the axialmovement of shaft 36 and sleeve26, vvithoutanyV change in angular velocity, it is necessary to build uplsufficient force as to result in an axialinovetion. As the'motionstarts, the increase-of spring tension is shown by line CD whileincreasing centrifugal force ment-of shaft r36 despite the increasedforce of spring' d8. f

Due to the cone shape of plate 24, theV axial push ,rey-y mainsproportional to the centrifugal force developed,

which increases accordingly. This result is achieved as a resultl ofthe'radial Vmovement, of balls 22, '22. The

centrifugal force is proportional to the radius of thecenter ofgravityofthe balls, vthe mass of said balls', Yand thesquare of theangular velocit;l thereof. Thus, since the weight or mass of the ballsis a constantfactor, and it .is undesirable to chanvgethe angularvelocity sincev to do so is inconsistent with the desired snap action,thevonly way`it is possible to secure anV increase in centrifugal forceis by an increase in the radialpositioning of the center of gravity ofthe balls. Such increase is obtained by form-` ing cone portion 30 ofsuch angularity that the ball movement between the governor in closedposition, as in Figure 1, and in openv position, where balls bearagainst the cylindrical ange 16, is large enough to insure the neededincrease. That is, the increase in the axial Vcomponent of the force ofthe balls 22 as they move radially outwardly against .the surface ofthec one 30 is greater than the increase in the force of the compressionspring 38 as the cone 30 moves axially toward the spring 38, thusresulting in the balls 22 and cone 30 jumping from one extreme positionto another.

With the structure of Figure l, the governor operates as follows: y

As long as angular velocity remains below the specific velocity, thegovernor remains closed, the preloaded spring being stronger than theaxial push of the centrifugal force. When the specitic velocity isreached, the motion starts, the force exerted by balls 22 developing toa point beyond that of the preload of the spring. This starting motionincreases both the spring resistance and the force exerted by balls 22;but as the latter increase is faster than the former, the startingmotion is accelerated, and the gov-v ernor jumps to its open positionkdespite the increased spring resistance. And as the balls reach thecylinder flange 16 and are held there by the continuing velocity, thegovernor stays open.

Figure 1A is a diagram showing the magnitude of all acting forces.Forces are plotted vertically against governor axial travel indicated asa between two extreme locations, al and a2. Line 1131 is the preloadedforce of spring 3S; BC is the force needed to overcome frictions; thusalC is the push developed by the centrifugal force at the specificvelocity at the starting point of mo#4 follows line CH. The shaded areashows the excess of centrifugal force over the spring force.

There is snap action'too in the return' motion from open to closedposition of the governor. Assuming that the governor is open, thevelocity being above the specific value, and that the velocitydecreases, the magnitude of the governor axial push is to be read on thevertical line Yn2,y andV goes down from the upper part of said line. Thecompressed spring resistance corresponds now to a2B2 with a frictionloss BZG. The return motion begins when the axial push value falls belowpoint G and is accelerated .because the slope of axial push decrease GKis more inclined than that of spring decrease GE. Thus the acting forcewhich in that way is delivered by the .spring takes advantage over theresisting one, now the governor axial push, and snap action is obtainedthis way too.

Hereaften line B1B2 will be referred to as spring characteristic, andlines CH or GK as governor characteristic,

it being understood that there is a governor characteristic for eachdirection o f motion if friction `is taken in consideration. g

It is essential,therefore, that in a governor with built in snaplaction, the slope of .the governor characteristic depending on balls orweights having radial travel must be greater than theV slope of thespring characteristic.

. v yIn Figure 2, is illustrated atwo-stage snap acting deviceV,contained wholly .within a vdouble governor; this device lis ldesignedin view to insure three operative positions, the governor jumping fromthe first to the second equilibrium positionv at specic velocity andfrom the second to .the

third equilibrium posi/tion at another specific velocity.

,Sjmilarparts are referred to by similar reference numerals (although.the effective members as 34,42, 44 and the like-havebeen omitted, aswill' be readily understood).

In this device,- a smallshell 14a'- is axiallyand lslidably mountedongvan 4extension v12a of shaft 12 for rotationl with cone 30 (as inFigure l). However, balls 22a, 22a, trapped within lshell 14aV aresmaller and lighter than the v masses 2,2, l,22,in shell 14.` In thiscase, masses 22, V22. will move outwardly first, at the first specicvelocity of shaft 12, shifting plate Z8 and vshell 14d attached theretoby collar 29 lengthwise of shafty12.- This'r'st step snap action will befollowed by a second snap action, when the second velocity of shaft 12is reached weights 22a, 22a thereupon shifting plate 23a still furthervaxially of the shafts and a second time creating a state of unbalanceas to overcome the increased tension of spring 38. .It is to be notedthat masses 22, 22a originally are equidistant from the axis ofrotation; but that at speed, theyameter; thus to insure two differentspecific velocities,l balls 22 must. be'spaced further from shaft i2axis than balls 22h, when both elementary governors are close l. Twoshells `14 and Mb are provided, plate of shell 14 being'secured to shellrdb for'nicvement therewith axially of shaft 12 and stub iZb bycollar'ZZ, masses 22b,"22b trapped in shell lid-b are closer to the axisof rotation than are masses 22, 22 in shell iii, "l'hus, masses 22, 22will, in response to speed increase the shaft 12, shift out first,creating a snap action movement of stub shaft Zb through collar 29h,shell Mb, plate 2gb and collar 26b.

l Herer as the starting radii of balls 22 and 22hA are :iframesdifferent, the aperture angles of cones and 30b must also be different.

Figure 4 is an illustration of a single governor giving three operativeor equilibrium positions with built-in snap action.

In Figure 4, a two stage three position operating device is illustrated,also wholly contained within the governor assembly, wherein shaft 40 hasa shell 42 secured thereto for rotation therewith, shell 40 having anannular flange 44. Within the recess of shell 42, a collar 46 isfastened to shaft 40 having Aradially extending slotted arms 48, 49,within which are trapped weighted balls or masses S0, 50. A plate 52 isprovided, axially slidable along shaft 40 and capped by a collar 54;Plate 52 isV flat adjacent the shaft, as at 56, but there are twosuccessive conical surfaces, one 58 of Vwider angle aperture than theother 60; as a result the axial component of the centrifugal force whichis transmitted to the plate 52 by the balls is relatively greater whenthe balls ride along surface 58 than when they ride along surface 6i).

Thus, when the yiirst specific velocity is reached, the balls jumpradially until they meet the second conical surface where they arestopped by the sudden decrease in the transmitted axial component of thecentrifugal force which does notexceed the force of the compressedspring 38 due to the change of the profile. This is the second operativeor equilibrium position of governor. But when the other specic velocityis reached, the increase of centrifugal force enables the balls to starta new jump until they reach the external flange 44, where they arestopped in the third operative or equilibrium position.

In this case, both stages have snap or step action if the less widelyopened cone 60 is designed as to give to this peculiar part of thegovernor a more inclined char acteristic than that of the spring.

To use the three equilibrium positions of said device in a practicalway, any kind of control member may be used. For instance, a rod 62 maybe disposed within and through the casing 64 of-said control mcmber,bearing against compression coilAspring 38. Three control positionsmaybe provided, within casing64, as at A, B, C. Thus, as in the lpositionof Figure `4, with masses 50, 5t) against plate portion 56,\rod 62 willoperate through position A. When shaft 40 reaches the iirst specificvelocity, masses 50 travel outwardly and against plate 52vat portion 58thereof, rod 62 is snap or step shifted to position B. Similarly, whenshaft 40 reaches the second specific velocity, masses 50, 50 bearingagainst conical surface 60 will move plate. 52 still furtheroutwardlyand rod 62. will shift to position C against the further compression ofspring 38.

As pointed out above, spring 38 and governor characteristic are suchthat as the governor speed increases from range to range, the springwill be overcome. suddenly each time, permitting the snap action changethrough rod 62.

The embodiments of Figures l, 2, 3 and 4 have in common the structuralsimilarity that an adequate travel of the masses outwardly from the axisof rotation, when a specific speed of rotation is reached, is directlyresponsible for the snap-action through the angled faces of the axiallyshiftable plates and a correct inside diameter of cylinder 16. Sometimesit is diilicult to build the snap action only on the travel of thegovernor masses. ure 5 shows, for instance, how a governor having hingedmasses may be disposed for snap action partly by the masses travel andpartly by increasing the force of the axial component of the centrifugalforce by an adequate design of a leverage system transforming thecentrifugal force into said axial force.

In its general construction, the governor is of one well known type.Rotatable shaft 70 has fixed thereon, for rotation therewith, a collar72 having radially extending split arms 74, 74 within which are pivotedmasses 76, 76. The masses are pivoted otfcenter, with longer portions 77extending rearwardly. The .shorter portions 78 have mounted at theirfront ends rollers 80, 8i). A circular plate 82 is provided, which maybe fiat, as shown in Figure 5, but which, within the scope of thepresent invention, may be conical or curved (not shown) to add anadditional effect to that of the linkage; plate 82 vhaving a recessednose portion 84 slidably fitting over a shaft extension 86 in line withshaft 7i). A lever arm 88 is pivoted as at 90, lever S8 being swingablebetween a rear stop 92 and a front stop94. A compression coil spring 96is provided, secured at one end to arm 88 and to a support 98 at itsother end, spring 98 being normally biased to urge arm 88 towards stop92 and nose 84. Plate 82 is axially slidable on shaft extension 86, butrotates therewith due to the slot and key connection as indicated at 99.

.lt is obvious that the electric ,signal 100 will not operate when thegovernor is closed, as in the position of Figure 5. When the governoropens, the angular motion of lever arm 88 completes the electricalcircuit putting the signal in operation. A snap or jump action isnecessary to insure a good make-and-break contact in the electricalcircuit.

Spring 96 will function to maintain lever arm 88, nose 84, plate 82 andmasses 76, 76 in the position of Figure 5 until the specific speed ofrotation of shaft 70 is attained, at which time masses 77, 77, bypivoting about the ends of arms 74, 74, begin to swing outwardly. Themasses 76 are so mounted and pivoted that upon the governor reaching itsspecific velocity the axial thrust of the centrifugal force on theweights 76 increases at a greaterrate than the opposing compressionspringV 96 Idue to both the increased centrifugal -force as the weights77 swing outwardly and the increased mechanical ad vantage as themovementy of the roller 80 approaches a path parallel to the plate 82.Consequently upon `the governor reaching its specific velocity, theplate 82 and hence treme position of open contacts to the other extremeposition of closed contacts.

When the contacts are lopen the center of gravity of Y the governormass77 is positioned as indicated at R1, the

Fis-

. dotted line leading to the pivot 79 representing the effective torquearm of the mass 77. As the mass center of gravity rotates about 79toiposition R2 the point of Vcontact between plate 82 and roller 80 hasa decreasing torque arm which becomes zero when the line of pivot 79andpin 81 is perpendicular to the plane of plate 82. Up to this positionthe more R1 is displaced in the direction of Ra the more effective arethe masses 77 incompressing spring 96.

The embodiment illustrated in Figure 5 is provided with a leveragesystem within the rotating portion of the governor in order to achievesuiicient axial thrust to overcome the initial and increased opposingforce of the antagonistic spring in order to obtain the snap actionbetween spaced equilibrium points. However, when space does not permitthe use of governors of this type, the effective snap action can stillbe obtained in accordance with my invention by disposing between thespring and the governor a linkage of such construction so as tomultiply'the effect of the movement of the governor control, in order toinsure the characteristics illustrated by the shaded areas in Figure la.

This linkage structure can be incorporated within the governor, orassociated with it externally. In Figure 5, the linkage structure isincorporated within the governor. In Figures 6 'to 12, the linkage isexternally located, but associated with the governor'.

Sometimes it may be necessary to use a governor like a ball governor inwhich no internal variable leverage can be used, while a lack of spacemay not permit the mass travel necessary for the desired snap action. Inthis case, a suitable mechanism may be located outside of the governorand cooperate and be associated therewith, as shown on Figures 6 to l2.

the control lever arm 88 will jump from the exmeshes 7 In this case, theexternal leverage acts all along the axial travel, providing amechanical advantage to the axial thrust or a disadvantage to the springaction in order to permit the axial thrust caused by the centrifugal`forces Y of the rotating `masses to increase -at a greater rate thanthe opposing antagonistic force thus effecting a snap or jump actionbetween two equilibrium positions.r

in all of the devices of Figures 6 to 12, the centrifugal 1 force isdeveloped within a shell as 110 secured to rotatrotational speedof shaft112, control member 116 is shifted outwardly of shell 11i?. However, itshould be noted that the centrifugal force of the balls 114 in thedevice illustrated in Figs. 6V and 7 does not, by itself, increasesutiiciently beyond the specific velocity to provide the snap actionachieved earlier. Hence, a mechanism must be provided to eifect a snapor jump action between positions of equilibrium in response to a forceor thrust increasing ata rate suicient to overcome the increasing7antagonistic force of the spring. This mechanism is provided externallyof the rotating portion of the governor. Figure 6l shows a two positiongovernor whose Vsnap acdoes lever arm 144 between-stops 152, 154'. Thisconstruction dilers from that of Fig. 6 in the leveragearrangement-which provides al lever for the axial push and anotherforthe spring.. It is apparent from Fig. 7 that, due to the inclination ofthe push lever 164 andof the spring lever 168, the axial-motion, whenthel governor overcomes the initial force of the spring 176, increasesthe effective length of the push and decreases the eliective lengthofthe spring lever, thus effecting the desired snap or step action betweentwo points.

in many installations, spring loaded centrifugal governors with snapaction are lused with complementary equipment. This equipment must Vnotinterfere with or prevent the desired snap-action, and, preferably,should complement same.

in 8 there is illustrated a single governor coupled with a leverageproviding-three spaced stepped operative positions, that is operatingwith snap action at two specic velocities. This construction is valuablewhen the governor cannot be built directly for more than two positions.The governor is shown at its closed position; a T-shaped lever Silwith anormal extension 394i terminating in a roller'3tl6, is freelyarticulated on a fixed pin 306, and receives the governor axial push. Atension spring 398 with Ya fixed end 311i, is attached to a second levcr252 freely articulated on a'iixed pin 316 yand this secondlever'actuates the control member 2l?. by a linlr tionis obtained bytheprovision of a mechanism of the VVaforesaid type in combination with agovernor har/inginsuilicient'thrust per se.

in the embodiment illustrated in Fig. 6, .a bell-crank 1d@ is provided,Ihaving angled v.arms 142, 144, the lever being pivotally fixed atv1r46.A tension coil spring 143,

securcdrto the end of arm' 314.2," urges arm 142 against plate lio, arm142 having Ya. roller 154i at its end in rolling contact with plate'116. Thevother arm 144 is trapped letween two stops152, '154, and has acontact' member 156 at its free end. As the resistance of spring 14S isovercome by the movementV of platev116 under the inflnenceof masses 114,114, Varm 144 is snapped over, about its pivot 146 for instance tocomplete a circuit between contact` 156 and a spaced contact 153.

in the above construction, the snap action is obtained upon thegovernor'reaching its specific velocity asa te# suit of the increasingcentrifugal derived thrust as the weights move outwardly and of theincreasing mechanical advantage ot the governor thrust over theantagonistic spring as the lever 142 is urged counter-clockwise. Whenthe governor overcomes the initial force of the spring 148, the arm 142rotates counter-clockwise about pivot 145 against spring 14S. However,this movement increases the component of the governor thrust acting inopposition to the antagonistic spring 148 at a greater rate than theincreased tension of the spring due to the change in ther'evolving angleof said thrust. This results in a v jump ofthe shell 116, crank 140 andcontact 156 from its initial equilibrium position to a second extremeposition l Vof equilibrium.

In Fig. 7, there is illustrated another embodiment of the presentinvention of the type illustrated in Fig. 6 in which a snap or jumpaction between twoequilibiium extreme positions is Vachieved by means ofa suitable variable mechanical advantage mechanism.' In this alternativeconstruction, an armed lever or crank 161) is pivoted at 162, and hasarm 16d;- with a roller 166 at its end bearing against platell, and anarm l at the other side bearing against a compression coil spring 170bearing against a support 15). The middle arm 182 is provided with acontact 184 acting as control member of the governor and in line with acontact 18S of an electrical circuit (not shown), branch 182 pivotingbetween stops 186, 188 as 250. Along the edge of lever 252 whichconfronts lever 3190, there are several spaced elevated fulcrum points3ft?. and 314. Whcnthe governor velocity, is below the lowest specii'icvelocity. both levers t'a'lie the position shown in Fig. 8, lever 252engagingy the lever Zilli through the fulcrumZ and stopped oy the hubvof said lever, due to spring action. rihe location of fulcrum` 312 andthe characteristics of spring 333 arersu'ch that when the tirst specificvelocity is reached; thefgovcrnor axial thrust rotates bothrlevcrsyandsaid levers rotate about their respcctivepivots and at the same timecanbe regarded as having angularV motion toward eachother about the movableulcrum-312 such that the fat faces forming an acute angle with fulcrum312 as a vertex suddenly snap together' in-a manner similar to theaction of elements 24:8 and 252 whichl are shown open in Figi?. andclosed in Fig. 1l., At the higher specific velocity,`both levers arerotated'again, but this time through the fulcrum 31.4, and assumes theposition shown in Fig. l2. The location of the fulcrums 312 and 314determines the higher specific velocity relatively tothe lower specificvelocity.

As can vbe seen in Figs. 8, ll and l2, the successive snap orstepactions at the first specific velocity about fulcrum 312 and at 'thesecond specific velocity about fulcrum 314i is achieved as a result ofboth the increased centrifugal derived thrust as the weights moveoutwardly and ofzthe increasing mechanical advantage of the goveinerthrust over the force of the antagonistic spring as the shell advancesaxially. ln thc lirst step the thrust transmission is through thefulcrum EEZ andin the second step it is through the fulcrum 314i. Asabove set forth, the characteristics of this system is determined by theconfiguration of the levers, the location of the ul crums, -the positionand strength of the spring and the y characteristics of' the rotatingportion of the governor.'

Some applications require a variable specific velocity withina givenrange as, for example, in snap-action governors for use in automaticautomotive transmissions. Fig.,9 illustrates a snap-action governor withexternally located cooperating linkage as applied to an automotivetransmission with two ditferent drive ratios, requiring al 9 erativevelocity is to add to the spring loaded governor 110 an auxiliarycontrol device such as a vacuum operated diaphragm which is responsiveto the degree of vacuum in the engine intake manifold and is a measureof the' power required by the drive of the automobile at a given time.

Referring to Fig. 9, the governor 110 is mounted on a rotatable shaft112 of the drive transmission preferably connected to the driven shaft.Near its center, or apex, governor control member 126 is flattened, andbears against a roller 262 mounted at the end of arm 204 of the bell.crankl which is rotatably pivoted by means of pin 206. A tension spring208 connects the end of arm 204 to a fixed point 2id, and is obliquelymounted urging the bell crank 200 in a clockwise direction. Theactuation of lever 200 by governor 110 is as described with respect toFig. 6.

Assuming that control of the transmission is effected through a controldevice 210, as for cxainple, an hydraulic oil distributor, having alaterally slidable 4rod 212, as the valve of said distributor, rod 212isconnected by link 214, to arm 216 of the bell crank 290. As the governorcontrol member 116 moves from one operative position to another, controlrod 212 is, or should have, two spaced operating positions which maycorrespond to two drive transmission ratios. If the spring-loadedgovernor 110 were the only means to cause change from one operativeposition to the other, this change would aways occur at `the samepredetermined R. P. M. and at the same specific angular velocity w. Thedown shift would aways occur at a little below w. v

The governor 110 and spring 208 are preferably so constructed that theangular velocity w corresponds to the minimum of car velocity at whichthe shifting is desired. VTo Vprovide the upper specitic velocity W,another tension spring 236 is added, with one .end secured 4to a fixedpoint 238 and the other end attached to a lever 232 freely articulatedon pin 266 on which leverr 200 also is'frree to rotate." To transmit theforce .of spring 236 to the governor,` lever 232 has a shoulder 234which is bent to engage the edge of arm 204 whereby a-clockwise forcemay be imparted to crank 260 in addition to that of spring 20S. 4

The vacuum equipment 222 is used to obtain all specific velocitiesbetween w and W, in operating the control 210. A closed chamber 222 isseparated into two parts by a flexible diaphragm 226, with the left partconnected to the intake manifold by a pipe 224, the other part-beingunder atmospheric pressure. VThe guide 228 of the diaphragm is connectedby a link 23d to lever 232, in such a manner as to have the torcecreated by the vacuum actingagainst the spring 236. Due to shoulder 234,the vacuum force cannot act on the governor', nor on spring 208, butonly reduce the action of spring 236. l

When the engine is operating at full power, throttle wide open, there isno appreciable vacuum in chamber 222, and both springs exert their fullstrength against lever arm 204. The shifting occurs at velocity W. Whenthe engine is operating at less than full power, throttle .only partopen, there is some degree of vacuum in chamber 222. The force of thevacuum exerts a pull on rod 228, link 230 and lever arm .232, therebyremoving some degree of pressure from spring 236 upon lever arm 204.Thus, the main crank .200 will jump from one to the other Yof itsequilibrium positions at a lower angular velocity. If engine load issmall enough because the throttle is lightly depressed, the vacuum inchamber 222 is sufficient to overcome spring 236 and eliminatecompletelythe effect of said spring as any factor in the spring loadingof lever 204. Under such conditions, only spring 208 will be effectiveand the shift will occur at the predeterminedvnumber of R. P. M. w. Andall intermediate `shifting velocitiesare possible becauserthe vac uumforce can take any intermediate value between its maximum and. itsminimum.

Athe governor when the upper specific velocity is If improperlydesigned, the vacuum may disturb the governor snapaction. At a givenengine or car velocity and at a given throttle opening, the rate of thevacuum is constant all along the control member stroke while thestrength of spring 236 increases when the governor opens. This wouldinterfere with the snap-action. To correct this situation, it isdesirable to provide to the subassembly comprising the vacuum device,lever 232 and spring 236 a decreasing mechanical advantage as the motionadvances to help the internal motion of said sub-assembly. This isobtained by any of the means explained before, for instance by aconvenient Obliquity given to both link 230 and spring 236 relatively tolever 232. Rods 230 and 260 may be controlled by the throttle oraccelerator pedal rather than by engine manifold vacuum acting upondiaphragms 226, if desired.

It is obvious in Fig. 9 that the increasing effective arm lever of thevacuum force when the governor opens, and the decreasing effective armlever of the spring encourage the snap or jump action of the system dueto the variation ot' interposed levers as explained. Outside of vacuumchamber, lever and spring, all other parts operate as explained forFigure 6.

ln cases where a transmission controlled by a governor has more than tworatios, three or more, the governor must be provided with three or moreoperative positions in addition to the variable speed dispositionexplained on Figure 9.

in Fig. l() is illustrated a three position governor arrangement for athree ratio transmission including the variable speed dispositions byvacuum with parts similar to other figures Abeing similarly numbered. Aninverted bell crank 240 is pivoted at 242. One arm 244 has a roller 246`at its end bearing against governor plate 116. The other, arm 248 ofcrank 240, normally depends at substantially right angles to shaft 112at its rest position. This construction is an equivalent of the T-shapedlever 300 of Fig. 8. Control mechanism 210 has shaft 212 projectingtherefrom and connected by link 250 to an arm 252 of a bell crank 254provided with an integral arm 258.v Diaphragm rod 228 is connected to alink 260 which is pivoted to lever 263 which in turn is pivoted 'to theljoint of crank 254. The lever 268 is provided with projecting ledge 270bearing on arm 258. Tension coil springs 272, 274' are secured to arms26S and 25S, and to fixed pins 276, 278 respectively. As governor plate116 is shifted outwardly on increase in rotation of shaft 112, acting onlever arm 244, lever 240 pivots about 242 and arm .248 is swung againsta corner 312 of an outwardly extending shoulder 280 on arm 252 saidshoulder having sharp corners or fulcrums 312 and 314. The firstVposition of the parts is illustrated in Fig. l0. This positioncorresponds to a governor velocity below the lower specific velocity.The second position is illustrated in Fig. ll, with arm 248 lying atlyagainst shoul* der y280 of arm 252, at which point control rod 212 isshifted vone vunit into sub-assembly 210. This position is obtained whengovernor velocity is between both specific velocities. As the lever arm244 is further actuated by reached, arm 248 shifts to the positionillustrated in Fig. l2, pivoting about the corner of shoulder 280 movingcontrol 212 still -further into the sub-assembly 212, the three controlLpositions being indicated, for instance, at I, K and L (Fig. l0).

All of the governors may be provided with restoring springs to return`them to a position of low or zero speed of rotation. However, spring308 preferably returns cone 116 as the governor force decreases. Spring96 can likewise return masses 77 unless R2 is permitted to move beyondthe point where the line of 79-81 is perpendicular to plate 82 so as tolock. The masses 7'7 vcould then be restored by a vspring acting betweenthem or manually lwith a lever controlled by the operator. Normally theposition Rz is sutiicient to close the contacts of circuit 10G andspring 96 can restore the masses 77. In Fig. 7

grasses as the governor force drops with the contacts 184, 85 closed,spring 7i) rotates arm lSZ clockwise and restores governor lill?. SpringMS has thesame action in Fig. 6 and also spring 20S `in Fig. 9 andspring274 in Fig. 10. The governor devices aretprimarily automatic controlmeans and are self-restoring- This structure is a combination of themulti-position device shown in Fig. 8 with the variable velocitydisposition explained in Fig. 9. Thus, all complementary explanationsgiven for such figures apply here, as apply all precautions to be takenrelatively to multiple positions and vacuum levers. The result is amultiple position yand variable angular velocity governor withsnapaction not impaired in'any way by any of the additions imposed uponby the special use o1" the governor.

lu summary, snapwaction can be built completely inside of any kind ofgovernor by designing the travel of center of gravity of masses longenough in accordance to the spring increase; this way, the snap-actionresults from an increase of radius of center of gravity of masses whichis faster than the increase of the force of thc antagonistic spring allalong the axial motion of the governor. This applies as well to singlegovernors with two operative positions, Fig. l, or with more than twopositions, Fig. 4, or to'more complicated governors like those shown inFigs. 2 and 3.

lf the travel of the masses cannot be built up enough to provide thewanted snap-action, an increase of the governor axial push relatively tothe centrifugal force can be produced in some kinds of governors bysimple alteration of the internal leverage transforming the centrifugalforce into the axial push ofy the governor-cxample, 1Eig. 5, relative toa hinged governor.-

lf both adequate masses travel and internal leverage cannot be designedas to insure completely the wanted snap-action, then an externalvariable leverage has toV be used. Figures 6 and 7 show this solutionfor a single A governor having two operative positions and Fig. 8 lfor asingle governor completed by a lever device conferringl to it more thantwo positions.

if one or several variable operating velocities are needed, and specialdevices added to the governor for this purpose, these devices like themulti-position mechanisms, mustV not bring trouble to the snap-actionand have to be carefully checked. The correct mounting of a variablevelocityl mechanism in supplement to yan external snapaction leverage isshown in Figure 9 with a single two position governor.

Gf course. some precautions have to be taken with any multiple positiondevice; Figures l0, ll and l2 show how to assemble correctly a variablevelocity mechanism and a multi-position device with a single governorprovided with an external snap-action leveraget I claim:

l. A governor mechanism of the type described comprising a rotatablemember, a weight eccentrically mounted relative to the axis of rotationof said member and adapted to rotate therewith, said member beingprovided with aradially extending guide engaging said weight andrestricting the path of movement thereof, a thrust member axiallyslidable relative to said rotatable member and having a portion thereofregistering with said guide and sloping toward the opposing portion ofsaid guide as said portion extends radially outwardly, a varyingmechanical advantage link mechanism and biased spring means having acharacteristic constant selected to provide a first rate of forceincrease and acting through said link mechanism urging said thrustmember toward said rotatable member whereby said sloped portion bearsagainst said weight, the

relative angle of said sloped portion with respect to theV axis ofrotation being such that for a velocity of rotation of said weightsequal to the specific governor velocity for the combination, thcreactive force required to be exerted on said conical surface tomaintain the weights in position increases at a rate greater thanrsaid'first rate of force l2 increase, said angle of slope and thecharacteristics of said link mechanism and said spring means being suchthat upon said rotatable member rotating at a predetermined speed thethrust imparted to said thrust member by said weights as a result of thecentrifugal force thereof is sutiicient to overcome the opposing thrustof the spring means through said link mechanism causing said thrustmember to recede from said rotatable member and permitting said weightto move radially outward, the rate of increase of the thrust due to theincreased centrifugal force on said weights as they move outwardly andthe increased mechanical advantage of said link mechanism in favor ofsaid thrust member being greater than the rate of increase of thrust ofthe opposing spring means thereby resulting in said thrust memberjumping in snap fashion from its initial point to a second point ofequilibrium where lthe force opposing further axial movement of thethrust member is at least equal to the centrifugal force derived thrust,said link mechanism comprising a pivoted bell crank having one armbearing against said thrust member and the other arm connected to saidspring means whereby upon rotation of said bell crank by said thrustmember the moment arm and relative tangential component of the thrust ofsaid thrust arm increases and the moment arm and relative tangentialcomponent of said spring means decreases and wherein means are providedfor varying the loading of said spring means in response to apredetermined control.

with a radially extending guide engaging said weight and restrictingthepath of movement thereof, a thrust member axially slidable relative toVsaid rotatable member and having a portion thereof registering with saidguide and sloping toward the opposing portion of said guide as saidportion extends radially outwardly, a varying mechanicalV Y advantagelink mechanism and biased spring means having a characteristic constantselected to provide a first rate of force increase and acting throughsaid link mechanism urging said thrust member toward said rotatablemember whereby said sloped portion bears against said weight, therelative angle of said sloped portion with respect to the axis ofrotation being such that for a velocity of rotation of said weightsequal to the specific governor velocity for thecombination, the reactiveforce required to be exerted on said conical surface to maintain theweights in position increases at a rate greater than said first rate offorce increase, said angle of slope and the characteristics of said linkmechanism and said spring means being such that upon said rotatablemember rotating at a predetermined speed the thrust imparted to saidthrust member by said weights a-s a result of the centrifugal forcethereof is suflicient to overcome the opposing thrust of the springmeans through said link mechanism causing said thrust member to recedefrom said rotatable member and permitting said weight to move radiallyoutward, the rate of increase of the thrust due to the increasedcentrifugal force on said weights as theyy move outwardly and theiucreased mechanical advantage of said link mechanism in favor of saidthrust member being greater than the rate of increase of thrust of theopposing spring means thereby resulting in said thrust member jumping insnap fashion from its initial point to `a second point of lequilibriumwhere the force opposing further axial movement of the thrust member isat least equal to .the centrifugal force derived thrust, said linkmechanism comprising a pivoted bell crank having a plurality of spacedfulcrum points on one arm thereof and having the other arm connected tosaid spring means, and a pivoted lever bearing against said thrustmember and engaging one of said fulcrum points furthest removed from thepivoted end of said bell crank when said governor mechanism is in rest`position and engaging at said second point of equilibrium another ofsaid fulcrum points more closely spaced to the pivoted end of said bellcrank the force of the thrust member being insufficient, at saidpredetermined speed, to overcome the force of the loaded spring meansthrough said other fulcrum point but upon said weights being rotated ata second greater predetermined speed -said thrust member jumps in snaplike fashion to a third equilibrium position in a manner similar to theaction from said initial position to said second equilibrium position.

3. A governor mechanism of the type described comprising a rotatablemember, a weight eccentrically mounted relative to the axis of rotationof said member and adapted to rotate therewith, said member beingprovided with a radially extending guide engaging said weight andrestricting the path of movement thereof, a thrust member axiallyslidable relative to said rotatable member and having a portion thereofregistering with said guide and sloping toward the opposing portion ofsaid guide as said portion extends radially outwardly, a varyingmechanical advantage link mechanism and biased spring means having acharacteristic constant selected to provide a first rate of forceincrease and acting through said link mechanism urging said thrustmember toward -said rotatable member whereby said sloped portion bearsagainst said weight, the

relative angle of said sloped portion with respect to the axis ofrotation being such that for a velocity of rotation of said weightsequal to the specific governor velocity for the combination, thereactive force required to be exerted on said conical surface tomaintain the weights in position increases at a rate greater than saidfirst rate of force increase, said angle of slope and thecharacteristics of said link mechanism and said spring means being suchthat upon said rotatable member rotating at a predeter mined -speed thethrust imparted to said thrust member by said weights as a result of thecentrifugal force thereof is suiiicient to overcome the opposing thrustof the spring means through said link mechanism causing said thrustmember to recede from said rotatable member and permitting said weightto move radially outward, the rate of increase of the thrust due to theincreased centrifugal force on said weights as they move outwardly andthe increased mechanical advantage of said link mechanism in favor ofsaid thrust member being greater than the rate of increase of thrust ofthe opposing spring means thereby resulting in said thrust memberjumping in snap fashion from its initial point to a second point ofequilibrium where the force opposing further axial movement of thethrust member is at least equal to the centrifugal force derived thrust,said link mechanism comprising a pivoted bell crank having a pluralityof spaced fulcrum points on one arm thereof and having the other armconnected to said spring means, and a pivoted lever bearing against saidthrust member and engaging one of said fulcrum points furthest removedfrom the pivoted end of said bell crank when said governor mechanism isin rest position and engaging at said -second point of equilibriumanother of said fulcrum points more closely spaced to the pivoted end ofsaid bell crank the force of the thrust member being insufiicient, atsaid predetermined speed, to overcome the force of the loaded springmeans through said other fulcrum point but upon said weights beingrotated at a second greater predetermined -speed said thrust memberjumps in snap like fashion to a third equilibrium position in a mannersimilar to the action from said initial position to said secondequilibrium position, and auxiliary second spring means responsive to acontrol device for imparting a supplementary variable moment to saidbell crank in the same direction as said first spring means thereby tocorrespondingly vary said first and second predetermined snap activatingspeeds.

4. A governor mechanism of the type described comprising a rotatablemember, a weight eccentrically mounted relative to the axis of rotationof said member and adapted to rotate therewith, said member beingprovided with a radially extending guide engaging said weight andrestricting the path of movement thereof, a thrust member axiallyslidable relative to said rotatable member and having a portion thereofregistering with said guide and sloping toward the opposing portion of-said guide as said portion extends radially outwardly, a varyingmechanical advantage link mechanism and biased spring means having acharacteristic constant selected to provide a first rate of forceincrease and acting through said link mechanism urging said thrustmember toward -said rotatable member whereby said sloped portion bearsagainst said weight, the relative angle of said sloped portion withrespect to the axis of rotation being such that for a velocity ofrotation of said weights equal to the specific governor velocity for thecombination, the reactive force required to be exerted on said conicalsurface to maintain the weights in position increase at a rate greaterthan said first rate of force increase, said angle of slope and thecharacteristics of said link mechanism and said spring means being suchthat upon said rotatable member rotating at a predetermined speed thethrust imparted to said thrust member by said weights as a result of thecentrifugal force thereof is sufficient to overcome the opposing thrustof the spring means through said link mechanism causing said thrustmember to recede from said rotatable member and permitting said weightto move radially outward, the rate of increase of the thrust due to theincreased centrifugal force on said weights as they move outwardly andthe increased mechanical advantage of said link mechanism in favor ofsaid thrust member being greater than the rate of increase of thrust ofthe opposing spring means thereby resulting in said thrust memberjumping in snap fashion from its initial point to a second point ofequilibrium where the force opposing further axial movement of thethrust member is at least equal to the centrifugal force derived thrust,said link mechanism comprising a pivoted bell crank having a pluralityof spaced fulcrum points on one arm thereof and having the other armconnected to said spring means, and a pivoted lever bearing against saidthrust member and engaging one of said fulcrum points furthest removedfrom the pivoted end of said bell crank when said governor mechanism isin rest position and engaging at said second point of equilibriumanother of said fulcrum points more closely spaced to the pivoted end ofsaid bell crank the force of the thrust member being insufficient, atsaid predetermined speed, to overcome the force of the loaded springmeans through said other fulcrum point but upon said weights beingrotated at a second greater predetermined speed said thrust member jumpsin snap like fashion to a third equilibrium position in a manner similarto the action from said initial position to said second equilibriumposition, and auxiliary second spring means responsive to the pressurein the intake manifold of an internal combustion engine for imparting asupplementary variable moment to said bell crank in the same directionas said first spring means thereby to correspondingly vary said firstand second predetermined snap activating speeds.

References Cited in the file of this patent UNITED STATES PATENTSRe.21,844 Vetter June 24, 1941 1,135,054 schacht Apr. 13, 1915 1,137,110Balough Apr. 27, 1915 1,844,674 Norris Feb. 9, 1932 2,088,427 MaurerJuly 27, 1937 2,109,615 Durham Mar. 1, 1938 2,187,207 McCabe Jan, 16,1940 2,207,340 Claus July 9, 1940 2,306,696 Hale Dec. 29, 1942 2,341,624Kieser Feb. l5, 1944 2,430,799 Aspinwall Nov. 11, 1947 2,495,617 WallaceIan. 24, 1950 FOREIGN PATENTS 465,593 Germany Sept. 26, 1928

